Biological samples, such as blood samples taken for drug discovery and saliva taken for DNA profiling in criminal investigations, are typically manually collected and placed on an absorbent storage medium, which may comprise a membrane impregnated with chemicals for stabilising the sample. The samples are allowed to dry and, once dry, the biological storage medium can be transported to a testing facility for analysis.
Such biological storage media are typically delicate, and require some kind of protective casing for handling and storage. Conventionally, such cases have been constructed of relatively thin, flexible cardboard; however, such cardboard cases suffer from a number of drawbacks. Firstly, cardboard is susceptible to damage by moisture; the constituent components of a cardboard case are likely to warp or even delaminate if the device comes into contact with water. Secondly, cardboard has a relatively low structural strength; rough handling during transport is likely to result in bending, tearing or crushing of the cardboard case. These defects may present problems in subsequent handling. For example, if the sample stored is a test sample, tests may be carried out using robotic or other automated handling systems. If, however, the storage medium and/or the protective case in which it is stored is not flat or is otherwise damaged, this may cause problems for the automatic handling system.
US20090117011A1 proposes a rigid holder into which the sample card and cardboard case may be inserted to protect it from mechanical damage during transportation. The construction of the device is such that it is also resistant to water to prevent it from warping if it gets wet. However, the rigid holder adds an additional structure to the sample storage device, making it complicated and expensive to manufacture and assemble. Further, the cardboard case and sample storage medium are simply inserted into the rigid holder by aligning the sample card with a groove in the rigid holder; this means that the cardboard case and sample card can easily be removed, or simply fall out during automated or other handling of the device; this may lead to samples being inadvertently misplaced or misdirected, with obvious undesirable consequences.
It is an object of the present invention to at least mitigate the problems of the prior art.
In addition, the device of the present invention is, not exclusively, intended for use with an automated punching system which will remove a piece of sample storage medium. Therefore, the device has to be rigid but the sample storage medium has to be assessable to the punching system. Since automated processing of the manually collected sample is envisaged, the need for communicating incorrect/insufficient/contaminated placement of the sample on the medium is desirable.